JP2015124283A - Curable epoxy resin composition and molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable epoxy resin composition that provides a cured molded article in which yellow discoloration is suppressed even when used for a long time under a high-temperature outdoor condition, and to provide a material suitably used for a structural material for outdoor use, an optical material, and a semiconductor material.SOLUTION: There is provided the curable epoxy resin composition obtained by blending: a modified epoxy resin (A) which is obtained by reacting a carboxylic acid compound (A3) with an epoxy resin (A4) having two or more epoxy groups in a molecule and not having an aromatic ring structure in the molecule, the carboxylic acid compound (A3) being obtained by reacting a polyol (A1) having alcoholic hydroxyl groups at molecular terminals and an acid anhydride (A2); a phenolic antioxidant (B) having a molecular weight of 500 to 1500; a curing agent (C); and a curing accelerator (D).

Description

  The present invention relates to an epoxy resin composition from which a cured product excellent in heat resistance and light resistance is obtained, and an optical material, a semiconductor material, and a composite material molded using the epoxy resin composition.

  Epoxy resins are used in many applications such as coatings, civil engineering, composite matrix, electronic substrate materials, semiconductor encapsulating materials, etc., because cured products with excellent adhesion, heat resistance, electrical properties, etc. can be obtained. ing. In particular, aromatic epoxy resins such as bisphenol A type diglycidyl ether, bisphenol F type diglycidyl ether, phenol novolac type epoxy resin, and cresol novolac type epoxy resin have water resistance, adhesiveness, mechanical properties, heat resistance, and electrical insulation. It is widely used in combination with various curing agents because of its excellent economic efficiency. However, these resins are susceptible to yellowing of molded products due to heat, ultraviolet rays, and the like, and there are restrictions in use for optical materials that require heat resistance and light resistance and for outdoor use that is exposed to sunlight.

  For the purpose of suppressing yellowing due to oxidative degradation under a thermal environment, a hindered phenol-based antioxidant is often added to the epoxy resin composition (Patent Document 1). However, because the hindered phenol type structure has high crystallinity and poor solubility in the epoxy resin matrix, the antioxidant is not dispersed uniformly during resin mixing or molding, and the crystals are aggregated. As a result, there is a problem of precipitation.

  Even if the antioxidant can be uniformly dispersed in the epoxy resin matrix, it will cause a phenomenon of bleed out in which the antioxidant will float on the surface of the molded product during long-term use, and it will gradually escape from the molded product. End up. Bleed-out tends to occur when an antioxidant having a low molecular weight as described in Patent Document 2 is used. In addition, bleed-out proceeds in a shorter time when using heat. For these reasons, when exposed to a long-term thermal environment, the effect of the antioxidant is attenuated and the molded product turns yellow.

  Patent Documents 3, 4 and 5 propose an epoxy resin composition using an antioxidant having a high molecular weight. However, these documents do not mention at all about the aggregation, precipitation and bleed-out of the antioxidant. In addition, the solubility of hindered phenolic compounds in non-aromatic epoxy resins is low, and the solubility is further reduced when phenolic antioxidants with high molecular weight are used. It is easy to cause. In addition, there is no specific description about the phenolic antioxidant having a molecular weight of 500 to 1500.

  On the other hand, in order to improve the impact resistance of a molded product obtained by curing the epoxy resin composition, a polyol component is often added to the curable epoxy resin composition. Patent Document 6 proposes an example in which a polyol compound is added to an epoxy resin composition to improve impact strength. Patent Document 7 proposes an example in which a polysiloxane polyol compound is added to an epoxy resin composition to reduce the internal stress of the cured product. Patent Document 8 proposes an example in which a polyol component such as polyester polyol is added to an epoxy resin composition to improve the flexibility and adhesiveness of the cured product. Patent Document 9 proposes an example in which a polyether polyol and an antioxidant are added to an epoxy resin composition to obtain an optically shaped article excellent in surface smoothness.

  Thus, although attempts have been made to add various polyol components to the epoxy resin composition, all are examples aimed at improving the toughness of the molded product, combined with an antioxidant having a high molecular weight, There are no examples focusing on attempts to solve the precipitation, crystallization, and bleed-out of antioxidants even in an environment exposed to light.

International Publication No. 2007/015426 Japanese Patent No. 4837664 JP 2012-41403 A Japanese Patent No. 5119364 Japanese Patent No. 5233379 JP 63-165426 A JP-A-6-1000076 Japanese Patent No. 4911252 Japanese Patent No. 4620380

  The present invention provides a curable epoxy resin composition that does not cause yellowing of a molded article even during long-term use under high temperatures and outdoors, and is suitable for structural materials, optical materials, and semiconductor materials for outdoor use. Intended to be used.

  As a result of studies conducted by the present inventors to solve the above-mentioned problems, the combination of a specific polyol component and an antioxidant causes precipitation of an antioxidant or bleeding out even when used for a long time. No epoxy resin composition was obtained, and it was found that the above-mentioned problem in which yellowing of the molded product was not observed even when used for a long time under high temperature and light exposure environment, and the present invention was completed. .

  That is, the present invention relates to an epoxy resin composition comprising a modified epoxy resin (A), a phenolic antioxidant (B) having a molecular weight of 500 to 1500, a curing agent (C), and a curing accelerator (D) as essential components. The modified epoxy resin (A) has an alcoholic hydroxyl group (A1) and an acid anhydride (A2), and the molar ratio of the hydroxyl group in the polyol (A1) to the acid anhydride group of the acid anhydride (A2) is 1. : Carboxylic acid compound (A3) obtained by addition reaction at a ratio of 0.7 to 2.0, and epoxy resin having two or more epoxy groups in the molecule and no aromatic ring structure in the molecule Modified epoxy resin (A) obtained by reacting (A4) with a molar ratio of the total amount of hydroxyl group and carboxyl group of carboxylic acid compound (A3) and epoxy group of epoxy resin (A4) of 1: 3 to 10 ) A curable epoxy resin composition according to.

（式中、Ｒ₁は独立にメチル基あるいはフェニル基を表し、Ｒ₂は独立に内部にエーテル結合性酸素原子を有していてもよい炭素数２〜２０の２価の炭化水素を表わし、ｎは０〜５０の整数を表す。） As said polyol (A1), what is at least 1 type chosen from the polysiloxane polyol represented by following General formula (1), and a polyester polyol, and a hydroxyl equivalent is 150-2000 g / eq, is mentioned preferably.

(In the formula, R ₁ independently represents a methyl group or a phenyl group, R ₂ independently represents a divalent hydrocarbon having 2 to 20 carbon atoms which may have an etheric oxygen atom therein, n represents an integer of 0 to 50.)

  As said epoxy resin (A4), what is an epoxy resin which has two or more epoxy groups and an isocyanuric ring in a molecule | numerator is mentioned preferably.

（式中、Ｒ₃は炭素数１〜６０の２価の炭化水素基を表し、内部にエステル結合性酸素原子を２〜８個有していても良い。Ｒ₄は独立に水素原子又は炭素数１〜６の１価の炭化水素基を表す。） As said phenolic antioxidant (B), the compound represented by following General formula (2) which has a spiro ring structure is mentioned preferably, and (A) component, (B) component, (C) component and ( It is desirable that the component (B) is 0.01 to 5.0 mass% with respect to the total amount of the component D).

(In the formula, R ₃ represents a divalent hydrocarbon group having 1 to 60 carbon atoms, and may have 2 to 8 ester-bonded oxygen atoms inside. R ₄ is independently a hydrogen atom or a carbon atom. Represents a monovalent hydrocarbon group of formula 1-6.)

  Preferred examples of the curing agent (C) include dicyandiamide, diaminodiphenyl sulfone, and acid anhydride curing agents. The curing accelerator (D) is preferably at least one selected from quaternary ammonium salts and quaternary phosphonium salts.

  The curable epoxy resin composition has a 1 mm-thick plate-like molded product obtained by molding this composition. The light transmittance at 450 nm is 80% or more, and the light transmittance at 750 nm is 85% T. It is desirable to satisfy the above. Further, the molded product obtained by curing and molding the curable epoxy resin composition has a light transmittance at 450 nm of 80% or more and a light transmittance at 750 nm of 85% T or more in a 1 mm thick plate shape. It is desirable to satisfy

  In the present invention, the polyol (A1) having an alcoholic hydroxyl group and the acid anhydride (A2) have a molar ratio of hydroxyl group to acid anhydride group of the acid anhydride in a polyol molecule of 1: 0.7 to A carboxylic acid compound (A3) obtained by addition reaction at a ratio of 2.0, and an epoxy resin (A4) having two or more epoxy groups in the molecule and having no aromatic ring structure in the molecule, After making the molar ratio of the total amount of the hydroxyl group and carboxyl group of the carboxylic acid compound (A3) and the epoxy group of the epoxy resin (A4) react at a ratio of 1: 3 to 10 to obtain the modified epoxy resin (A), A curable epoxy resin composition characterized in that a phenolic antioxidant (B) having a molecular weight of 500 to 1500 is mixed and uniformly dissolved, and further a curing agent (C) and a curing accelerator (D) are mixed. It is a manufacturing method of a thing.

  Said curable epoxy resin composition is excellent as any of the resin composition for optical components, the resin composition for electronic components, or the resin composition for composite materials. It is excellent as a white resin composition for optical semiconductor devices containing a white pigment and an inorganic filler, or a resin composition for fiber reinforced composite materials containing reinforcing fibers. Moreover, this invention is a hardened | cured material formed by shape | molding and hardening | curing the said curable epoxy resin composition.

  From the epoxy resin composition of the present invention, a molded product having excellent heat resistance, light resistance and transparency, and less yellowing even when used for a long period of time in an environment exposed to high temperature and light is obtained. In particular, it is excellent as a reflector that is a reflection member of an apparatus including an optical semiconductor element such as an LED.

Hereinafter, embodiments of the present invention will be described in detail.
The curable epoxy resin composition of the present invention comprises a modified epoxy resin (A), a phenolic antioxidant (B) having a molecular weight of 500 to 1500, a curing agent (C), and a curing accelerator (D) as essential components. To do. Hereinafter, the modified epoxy resin (A), the phenolic antioxidant (B) having a molecular weight of 500 to 1500, the curing agent (C) and the curing accelerator (D) are respectively represented by the component (A), the component (B), ( Also referred to as component C) and component (D).

  The modified epoxy resin (A) used in the present invention comprises a polyol (A1) having an alcoholic hydroxyl group at the end of the molecule, a carboxylic acid compound (A3) obtained from an acid anhydride (A2), and an epoxy resin (A4). Although it is a thing obtained by making it react, if it is equivalent, it will not be restricted to the modified epoxy resin obtained by this manufacturing method.

  The reaction between the polyol (A1) and the acid anhydride (A2) is a reaction between the hydroxyl group of the polyol (A1) and the acid anhydride group of the acid anhydride (A2). This is a reaction in which a carboxyl group is generated at the terminal. If the hydroxyl group of the polyol represented by the following general formula (3) is a mole and the acid anhydride group of the acid anhydride represented by the following general formula (4) is b mole, b / a (molar ratio) is 0.7-2.0. The hydroxyl group and the acid anhydride group react one-on-one to obtain a carboxylic acid compound represented by the following general formula (5). The theoretical amount of the acid anhydride group necessary for esterifying the hydroxyl group is b / a = 1.0. When b / a is 0.7 or more and less than 1.0, the carboxylic acid obtained by the reaction A hydroxyl group remains in the compound (A3). On the other hand, when b / a exceeds 1.0 and is 2.0 or less, an acid anhydride group remains in the carboxylic acid compound (A3) obtained by the reaction. Here, the acid anhydride group of the acid anhydride (A2) has a cyclic structure as shown in the general formula (4).

（式中、ｘは平均２〜４を表す。Ｒ₅はｘ価の有機残基を表し、内部にＳｉ−Ｏ結合、エーテル結合性酸素原子、またはエステル結合を有していても良い。）

（式中、ｙは平均１〜２を表す。Ｒ₆は炭素数２〜１２の有機残基を表し、内部に脂環構造や縮環構造、アルキル基、アルケニル基、アルキニル基、カルボキシル基、ケトン基、アルデヒド基、エーテル結合やエステル結合を有していても良い）

（式中、ｘ、Ｒ₅、Ｒ₆は、一般式（３）、（４）のそれらと同意である。）
なお、一般式（５）は、一般式（４）におけるｙが１である場合の例を示す。

(In the formula, x represents an average of 2 to 4. R ₅ represents an x-valent organic residue, and may have a Si—O bond, an ether-bonded oxygen atom, or an ester bond inside.)

(Wherein y represents an average of 1 to 2, R ₆ represents an organic residue having 2 to 12 carbon atoms, and an alicyclic structure, a condensed ring structure, an alkyl group, an alkenyl group, an alkynyl group, a carboxyl group, (It may have a ketone group, aldehyde group, ether bond or ester bond)

(In the formula, x, R ₅ and R ₆ are the same as those in the general formulas (3) and (4).)
In addition, General formula (5) shows the example in case y is 1 in General formula (4).

  As the polyol (A1), various compounds can be selected as long as they are known, and two or more kinds may be used in combination. For example, polyether polyol, polybutadiene polyol, polyester polyol, polycaprolactone polyol, polycarbonate polyol, polysiloxane polyol, dimer diol can be mentioned, especially when using polyester polyol or polysiloxane polyol, in addition to heat resistance and light resistance, A cured product excellent in low water absorption is obtained, and the effect of uniformly dissolving the phenolic antioxidant is also high and desirable.

  Moreover, among these polyols (A1), it is preferable to be selected from polysiloxane polyols represented by the above general formula (1) and polyester polyols. Polysiloxane polyol can give a cured product particularly excellent in flexibility and light resistance, and polyester polyol can obtain a cured product excellent in weather resistance.

  The hydroxyl equivalent of the polyol (A1) is preferably 150 to 2000 g / eq, preferably 150 to 1500 g / eq, more preferably 200 to 1000 g / eq. Within this range of hydroxyl equivalents, the phenolic antioxidant (B) having a molecular weight of 500-1500 can be uniformly dissolved, and in addition to being able to suppress precipitation accompanying bleedout and crystallization of the antioxidant, the resulting modification The epoxy equivalent of the epoxy resin (A) does not become too large, and a cured product having a high glass transition temperature is obtained by blending and molding with a curing agent and exhibits good heat resistance.

  As the acid anhydride (A2), various compounds can be selected as long as they are known, and two or more kinds may be used in combination. For example, succinic anhydride, maleic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, nadic anhydride, hydrogenated nadic anhydride, trimellitic anhydride, hydrogenated trimellitic anhydride, pyrone anhydride Mellitic acid, hydrogenated pyromellitic anhydride, cyclopentanetetracarboxylic dianhydride and the like can be applied. In particular, preferred acid anhydrides (A2) for obtaining a modified epoxy resin (A) excellent in heat resistance and light resistance in the present invention are hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, hydrogenated nadic anhydride, hydrogen Alicyclic compounds such as hydrogenated trimellitic anhydride, hydrogenated pyromellitic anhydride, and cyclopentanetetracarboxylic dianhydride.

  The hydroxyl group of the polyol and the acid anhydride of the acid anhydride when the carboxylic acid compound (A3) represented by the general formula (5) is obtained by addition reaction of the hydroxyl group of the polyol and the acid anhydride group of the acid anhydride. The molar ratio of the groups needs to be reacted at a ratio of 1: 0.7 to 2.0. When the molar ratio of the hydroxyl group of the polyol to the acid anhydride group of the acid anhydride is less than 1: 0.7, the amount of the alcoholic hydroxyl group remaining in the carboxylic acid compound (A3) obtained by the reaction increases. Since the reactivity between the alcoholic hydroxyl group and the epoxy group is low, the carboxylic acid compound (A3) not bonded to the epoxy resin (A4) tends to remain when reacted with the epoxy resin (A4). Wake up. Further, when the molar ratio of the hydroxyl group of the polyol to the acid anhydride group of the acid anhydride exceeds 1: 2.0, the amount of the acid anhydride group remaining in the carboxylic acid compound (A3) obtained by the reaction is large. Thus, when reacted with the epoxy resin (A4), the crosslinking density becomes too high, causing gelation.

  The modified epoxy resin (A) obtained by reacting the carboxylic acid compound (A3) with an epoxy resin (A4) having an average of two or more epoxy groups in the molecule and having no aromatic ring structure in the molecule, The ratio (d / c) of the amount c mol of the carboxyl group in the component (A3) and the amount d mol of the epoxy group in the component (A4) needs to be reacted at a ratio of 3 to 10. When the reaction is carried out at a molar ratio d / c of less than 3, the resulting modified epoxy resin (A) has a very high molecular weight, resulting in a markedly increased viscosity and difficult handling. When the molar ratio d / c is reacted in excess of 10, the residual amount of the epoxy resin (A4) that does not react with the carboxylic acid compound (A3) increases, and the phenolic antioxidant (B) having a molecular weight of 500 to 1500 described later. And the compatibility of the component (B) becomes difficult to disperse uniformly.

  The epoxy resin (A4) needs to have an average of two or more epoxy groups in the molecule. When the number of epoxy groups in the molecule is less than 2, all the epoxy groups in the component (A4) easily react with the carboxy group of the carboxylic acid compound (A3). When such a component is blended with a curing agent and cured, it remains in the cured product as an uncrosslinked component and is undesirable because it causes surface stickiness.

  The epoxy resin (A4) needs to have no aromatic ring structure in the molecule. Although the aromatic ring structure is rigid and can be incorporated into the molecule to increase the glass transition temperature, it is derived from the conjugated structure, has a maximum absorption spectrum at about 260 nm, and exhibits a function of electron withdrawing and electron donating. When the group is present in the aromatic ring, the absorption spectrum tends to shift further to the higher wavelength side. Since there is light of 300 nm or more in sunlight, if it has an aromatic ring structure, it becomes easier for molecules to absorb light, causing an oxidative degradation reaction associated with electronic excitation and causing coloration due to the extension of the conjugated structure. Not desirable.

  As long as the epoxy resin (A4) satisfies the above, various compounds can be selected and two or more types may be used in combination. For example, 2,2-bis (4-hydroxycyclohexyl) propane diglycidyl ether, trimethylolpropane polyglycidyl ether, polypropylene glycol diglycidyl ether, hexahydrophthalic acid diglycidyl ester, triglycidyl isocyanurate, triglycidyl isocyanurate 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol, 3 ′, 4′-epoxycyclohexanecarboxylic acid 3,4-epoxy And cyclohexylmethyl. In particular, the preferred epoxy resin (A4) for obtaining the modified epoxy resin (A) having excellent heat resistance and light resistance in the present invention is a rigid structure and has an absorption spectrum maximum of about 220 nm, which is in a low wavelength region. A polyfunctional epoxy compound having a ring is desirable, and tris- (2,3-epoxypropyl) -isocyanurate represented by the following general formula (6) or glycidyl of tris- (2,3-epoxypropyl) -isocyanurate A modified product in which a part of the group is replaced with the functional group of the general formula (7) is preferable in terms of heat resistance.

（式中、Ｒ₇はそれぞれ独立にアルキル基、アルケニル基、アルキニル基、アリール基、アラルキル基、複素環基、又はそれらのハロゲン化、アミノ化、若しくはニトロ化誘導体である。）

(In the formula, each R ₇ independently represents an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, a heterocyclic group, or a halogenated, aminated, or nitrated derivative thereof.)

  The conditions for reacting the carboxylic acid compound (A3) and the epoxy resin (A4) are not particularly limited because they are general reactions of carboxyl and epoxy groups, but the reaction temperature is usually 50 ° C. It is -230 degreeC, Preferably it is 70 to 170 degreeC. If it is less than 50 ° C., the reaction time becomes longer, which is not preferable. On the other hand, if the temperature exceeds 230 ° C., the resin decomposes or causes side reactions during the reaction, which is not preferable.

  Although this reaction can be performed without a catalyst, it is preferable to use a catalyst from the viewpoint of shortening the reaction time. As such a catalyst, if it has an effect which accelerates | stimulates reaction of carboxyl and an epoxy group, various compounds can be selected with a well-known thing. For example, imidazole compounds and their salt compounds. Although a tertiary amine compound, a tertiary phosphine compound, a quaternary ammonium salt compound, a quaternary phosphonium salt compound, etc. are raised, it is not limited to these, You may use 2 or more types together as needed. Preferred compounds are quaternary ammonium salt compounds and quaternary phosphonium salt compounds from the viewpoint of suppressing coloring during the reaction.

  When using the above catalyst, the amount to be used is not particularly limited, but when the resulting modified epoxy resin (A) is 100 parts by mass, it is usually 0.001 part by mass to 3 parts by mass, preferably 0.005 part by mass to 1 part by mass. A method may be used in which a solution is prepared in advance using a solvent that dissolves the catalyst when the catalyst is added, and the catalyst solution is charged into the reaction system.

  Moreover, you may react by adding antioxidant from a viewpoint which prevents the coloring at the time of reaction of a carboxylic acid compound (A3) and an epoxy resin (A4). As this antioxidant, various compounds can be applied as long as they are known. For example, 2,6-t-butyl-p-cresol, butylhydroxyanisole, 2,6-t-butyl-p-ethylphenol, stearyl-β- (3,5-di-t-butyl-4-4 Monophenols such as hydroxyphenyl) propionate, 2,2-methylenebis (4-methyl-6-tert-butylphenol), 2,2-methylenebis (4-ethyl-6-tert-butylphenol), 4,4′-thiobis Bisphenols such as (3-methyl-6-tert-butylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2 , 4,6-Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis [methylene-3- (3,5-di-t-butyl-4- Droxyphenyl) propionate] high molecular phenols such as methane, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (3,5-di-t-butyl 4-hydroxy Benzyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, oxaphos such as 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide Faphenanthrene oxides, dilauryl 3,3′-dilauryl 3,3′-thiodipropionate, dimyristyl 3,3′-dilauryl 3,3′-thiodipropionate, distearyl 3,3′-dilauryl 3,3 '-Thiodipropionate, pentaerythrityl tetrakis (3-laurylthiop And ester skeleton-containing thioether compound-based antioxidants such as (Lopionate). Two or more of these antioxidants may be used as necessary.

  When the above antioxidant is used, the addition amount is not particularly limited, but when the obtained modified epoxy resin (A) is 100 parts by mass, 0.001 part by mass to 5.0 parts by mass, preferably 0.005 part by mass. It is desirable to add part to 2.0 parts by weight.

  The phenolic antioxidant (B) contained in the curable epoxy resin composition of the present invention has a molecular weight of 500 to 1500, and various compounds can be selected as long as it functions as a phenolic antioxidant. When the molecular weight is less than 500, a bleedout in which a low molecular weight component floats on the material surface from the matrix is likely to occur. In addition, a phenolic antioxidant having a molecular weight exceeding 1500 has low compatibility with the structure of the polyol used in the present invention, and is non-uniform in the matrix and easily causes precipitation due to crystallization.

  Specific examples of the phenolic antioxidant (B) include tris (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, 1,3,5-trimethyl-2,4,6-tris ( 3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, stearyl-β- (3,5 -Di-t-butyl-4--4-hydroxyphenyl) propionate, 2,2'-thiodiethylbis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythrityl- Tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], N, N ′-(1,6-hexanediyl) bis [3,5-bis (1,1-dimethylethyl) ) -4-Hydroxybenzenepropanamide], 6-t-butyl-4- [3- (2,4,8,10-tetra-t-butyldibenzo [d, f] [1,3,2] dioxa Phosphepin-6-yloxy) propyl] -o-cresol, 3,9-bis (2- (3- (3-tetrabutyl-4-hydroxy-5-methylphenyl) propionyloxy) -1,1-dimethylethyl ) -2,4,8,10-tetraoxaspiro [5.5] undecane and the like.

  It is more desirable to use a phenolic antioxidant having a spiro ring structure in the molecule as the phenolic antioxidant (B). These antioxidants have high compatibility with the polyol structure, and can suppress the ease of crystallization of the hindered phenol structure.

Among the phenolic antioxidants, a particularly preferred structure for obtaining the effect of the present invention is a phenolic compound represented by the general formula (2), and a particularly preferred structure is represented by the following formula (8). 3,9-bis (2- (3- (3-tetrabutyl-4-hydroxy-5-methylphenyl) propionyloxy) -1,1-dimethylethyl) -2,4,8,10-tetraoxaspiro [5 -5] Undecane.

  The addition amount of the phenolic antioxidant (B) is 100 parts by mass of the total amount of the modified epoxy resin (A), the phenolic antioxidant (B), the curing agent (C), and the curing accelerator (D). It is preferable to set it as 0.01-5.0 mass parts, especially 0.1-3.0 mass parts. If the addition amount is less than 0.01 parts by mass, sufficient heat resistance cannot be obtained, and yellowing easily occurs. If the amount added exceeds 5.0 parts by mass, it cannot be uniformly dissolved in the epoxy resin composition, and it tends to cause white turbidity and turbidity due to precipitation and crystallization of the antioxidant. The transparency of things is impaired.

  As the curing agent (C) contained in the curable epoxy resin composition of the present invention, a compound known as an epoxy resin curing agent can be used. For example, dicyandiamide, diaminodiphenylsulfone, adipic acid dihydrazide, sebacic acid dihydrazide, dodecanediohydrazide, isophthalic acid dihydrazide, succinic anhydride, maleic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methylated hexahydrophthalic anhydride, nadic anhydride Acid, hydrogenated nadic anhydride, trimellitic anhydride, hydrogenated trimellitic anhydride, pyromellitic anhydride, hydrogenated pyromellitic anhydride, cyclopentanetetracarboxylic dianhydride, etc. Two or more types may be used accordingly. In particular, dicyandiamide and diaminodiphenyl sulfone are preferably used in order to further satisfy mechanical properties such as fracture toughness and tensile properties in addition to light resistance in the present invention, and optical properties such as light resistance, transparency and heat resistance are preferred. In order to satisfy the requirements, it is preferable to use an acid anhydride-based curing agent such as hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, or hydrogenated nadic anhydride.

  The content of the curing agent (C) contained in the curable epoxy resin composition is such that the epoxy group of the component (A) and the active hydrogen or the acid anhydride group in the component (C) are 0.7 to 1 in an equivalent ratio. .4 is preferable. Outside this range, unreacted epoxy groups after curing, or active hydrogen in component (C) or acid anhydride groups remain and behave as uncrosslinked components, so the hardness and glass transition temperature when cured products are obtained. Is not preferable.

  As the curing accelerator (D), a compound known as an epoxy resin curing accelerator can be used. Examples include tertiary amines and salts thereof, imidazoles and salts thereof, organic phosphine compounds and salts thereof, and organic metal salts such as zinc octylate and tin octylate. Two or more kinds may be used as necessary. . Particularly preferred curing accelerators for obtaining the effects of the present invention are quaternary ammonium salts, organic phosphine compounds, and quaternary phosphonium salts. By using these, a molded article excellent in transparency, heat resistance or light resistance can be obtained.

  The content of the curing accelerator (D) contained in the curable epoxy resin composition is the sum of the modified epoxy resin (A), the phenolic antioxidant (B), the curing agent (C), and the curing accelerator (D). The amount is preferably 0.005 to 6.0 parts by mass, more preferably 0.1 to 3.0 parts by mass with respect to 100 parts by mass. When the addition amount is less than 0.005 parts by mass, the curing rate is slow under the curing conditions carried out in the present invention, and a long curing time of 20 hours or longer is required, which is disadvantageous in terms of economy. When the addition amount exceeds 5.0 parts by mass, the curing rate is too high under the curing conditions carried out in the present invention, and the productivity of a stable molded product is impaired.

  In the method for producing a curable epoxy resin composition of the present invention, a carboxylic acid compound (A3) obtained by addition reaction of a polyol (A1) and an acid anhydride (A2) is reacted with an epoxy resin (A4). After obtaining the modified epoxy resin (A), the phenolic antioxidant (B) having a molecular weight of 500 to 1500 is mixed and uniformly dissolved, and then the curing agent (C) and the curing accelerator (D). Mix. By carrying out such a production method, it is possible to suppress crystal precipitation of the phenolic antioxidant (B) during handling of the curable epoxy resin composition or during the curing process. In addition, a transparent molded article free from crystal precipitation of the phenolic antioxidant (B) can be obtained even when the curable epoxy resin composition is stored or a molded article is produced.

  The curable epoxy resin composition of the present invention contains the above components (A), (B), (C), and (D) as essential components, but it is preferable for those skilled in the art to adjust the viscosity and the curing rate. Therefore, as the component (E), other epoxy resins or epoxy compounds having two or more epoxy groups in one molecule other than the component (A) may be used within a range that does not impair the purpose and effect.

（式中、Ｒ₈は炭素数１〜２０の２価の炭化水素基を表し、内部にエーテル結合性酸素原子、及びエステル結合を有していても良い。） Examples of the component (E) include epoxy resins derived from monocyclic dihydric phenols such as resorcinol, hydroquinone, 2,5-di-t-butylhydroquinone, and epoxy resins obtained by nuclear hydrogenation of the aromatic ring. Epoxy resins derived from naphthalenediols such as 1,3-naphthalenediol, 1,4-naphthalenediol, 1,5-naphthalenediol, 1,6-naphthalenediol, 2,7-naphthalenediol, and the like Epoxy resin with ring hydrogenated, 4,4′-isopropylidenediphenol, 4,4′-isopropylidenebis (2-methylphenol), 4,4′-isopropylidenebis (2,6-dimethylphenol) 4,4′-dihydroxydiphenylmethane, 4,4′-dihydroxy-3,3′-dimethyldiphe Rumethane, 4,4′-dihydroxy-3,3 ′, 5,5′-tetramethyldiphenylmethane, 4,4′-secondary butylidenebisphenol, 4,4′-isopropylidenebis (2-t-butylphenol), 4 , 4′-cyclohexylidenediphenol, epoxy resin derived from bisphenols such as 4,4′-butylidenebis (6-tert-butyl-2-methyl) phenol, and epoxy resin obtained by nuclear hydrogenation of the aromatic ring And alicyclic epoxy resins listed in the general formula (9), and the like, but not limited thereto, two or more kinds may be used as necessary.

(In the formula, R ₈ represents a divalent hydrocarbon group having 1 to 20 carbon atoms, and may have an etheric oxygen atom and an ester bond therein.)

  The curable epoxy resin composition according to the present invention may contain various antioxidants different from the phenolic antioxidant (B) within a range that does not impair the purpose and effect, and particularly at the time of molding the resin composition. For the purpose of preventing coloring, phenol-based, phosphorus-based and sulfur-based antioxidants can be used. Each content of these three antioxidants is 100 parts by mass with respect to a total amount of 100 parts by mass of the modified epoxy resin (A), the phenolic antioxidant (B), the curing agent (C), and the curing accelerator (D). Each is preferably 0.01 to 6.0 parts by mass, and specific examples of the compound include the following antioxidants.

  Examples of phenolic antioxidants include 2,6-t-butyl-p-cresol, butylhydroxyanisole, 2,6-t-butyl-p-ethylphenol, 2,2-methylenebis (4-methyl-6-t- Butylphenol), 2,2-methylenebis (4-ethyl-6-tert-butylphenol), 4,4'-thiobis (3-methyl-6-tert-butylphenol), etc., as a phosphoric antioxidant, triphenyl phosphite , Diphenylisodecyl phosphite, phenyl diisodecyl phosphite, tris (nonylphenyl) phosphite, diisodecyl pentaerythritol phosphite, tris (2,4-di-t-butylphenyl) phosphite, bis [2-t-butyl- 6-Methyl-4- {2- (octadecyloxycarbonyl) ethyl} fe Hydrogen phosphite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (3,5-di-t-butyl 4-hydroxybenzyl) -9,10-dihydro -9-oxa-10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and the like, dilauryl 3, 3'-dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-dilauryl 3,3'-thiodipropionate, distearyl 3,3'-dilauryl 3,3'-thiodipropionate, penta An erythrityl tetrakis (3-lauryl thiopropionate) etc. are mentioned. Two or more of these antioxidants may be used as necessary.

  The curable epoxy resin composition in the present invention may contain an ultraviolet absorber as long as the purpose and effect are not impaired. Especially in applications where light resistance is more important than heat resistance, benzophenone-based, benzotriazole-based A hindered amine-based UV absorber can be used. Each content of these three kinds of ultraviolet absorbers is 100 parts by mass with respect to the total amount of the modified epoxy resin (A), the phenolic antioxidant (B), the curing agent (C), and the curing accelerator (D). It is preferable to set it as 0.01-6.0 mass parts, respectively, and the following ultraviolet absorbers are mentioned as a specific example of a compound.

  Examples of benzophenone ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2′-dihydroxy- As a benzotriazole ultraviolet absorber, such as 4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, 2- (2′-hydroxy- 5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-t-butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) benzotriazole , 2- (2'-hydroxy-3 ' t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole, 2- (2'- Hydroxy-3 ′, 5′-di-t-amylphenyl) benzotriazole, 2-{(2′-hydroxy-3 ′, 3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimidomethyl)- As hindered amine ultraviolet absorbers such as 5′-methylphenyl} benzotriazole, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6- Pentamethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) [{3,5-bis (1,1-dimethylethyl) -4-hydroxif Sulfonyl} methyl] butyl malonate, and the like. Two or more kinds of these ultraviolet absorbers may be used as necessary.

  Moreover, another curable resin can also be mix | blended with the curable epoxy resin composition of this invention. Such curable resins include unsaturated polyester resins, curable acrylic resins, curable amino resins, curable melamine resins, curable urea resins, curable cyanate ester resins, curable urethane resins, curable oxetane resins, Examples include, but are not limited to, curable epoxy / oxetane composite resins.

  When the curable epoxy resin composition of the present invention is cured and formed into a 1 mm-thick flat plate-shaped product, the light transmittance at 450 nm of the flat molded product is 80% or more, and the light transmittance at 750 nm. Is desirably 85% or more. As a method for evaluating the colorless transparency of the molded product, the light transmittance at 450 nm is measured using an ultraviolet-visible spectrophotometer with an integrating sphere. If the light transmittance at 450 nm is 80% or more, it is a transparent cured product without yellowing of the molded product, and if the light transmittance is less than 80%, the molded product is yellowed, or a phenolic antioxidant. It is suggested that crystals are precipitated without being uniformly dissolved, easily absorbs light having a short wavelength, and turns yellow when the molded product is exposed to light for a long time. Further, if the light transmittance at 750 nm is 85% or more, it is confirmed that the molded product is a transparent molded body without crystal precipitation of the phenolic antioxidant, and if the light transmittance is less than 85%, the phenolic oxidation is confirmed. Since the inhibitor is not dissolved uniformly and crystals are precipitated, the effect of the antioxidant cannot be expected, and the molded body is yellowed when exposed to heat or light for a long time. The production conditions, measurement conditions, and the like of the molded product used for the measurement of the light transmittance follow those described in the examples.

  The method for producing a molded body from the curable epoxy resin composition of the present invention is not particularly limited, but after casting the resin composition into a liquid and pouring it into a mold, a casting method for obtaining a cured product by heating, Dilute the resin composition with a solvent that does not contribute to the reaction, coat the film on the fluororesin plate, volatilize the solvent to form a film, and then laminate the films and pressurize and heat with a hot press By a press molding method for obtaining a cured molded body by simultaneously performing, a transfer molding method in which a resin composition is heated to be pre-cured and solidified, pulverized and powdered, and then charged into a transfer molding machine and thermoformed. Molding is preferable because a cured product having high dimensional stability is obtained.

  These curable epoxy resin compositions can be suitably used for a resin composition for optical parts, a resin composition for electronic parts, or a resin composition for composite materials, and is particularly useful as a resin composition for optical semiconductor parts. .

  Further, these curable epoxy resin compositions can contain white pigments such as titanium oxide, aluminum oxide and magnesium oxide, and inorganic fillers such as hollow silica and fused silica typified by silicon oxide. Therefore, it can be suitably used as a white resin composition for optical semiconductor devices having excellent heat resistance and light resistance.

  These curable epoxy resin compositions can contain reinforcing fibers such as glass fibers, carbon fibers, and aramid fibers, and thus can be suitably used as fiber-reinforced composite materials having excellent heat resistance and light resistance. it can.

  These curable epoxy resin compositions become a cured product by heat molding.

  Next, the present invention will be specifically described based on examples, but the present invention is not limited to the following examples unless it exceeds the gist. In addition, the part which shows a compounding quantity is a mass part unless there is particular notice. The unit of hydroxyl equivalent is g / mol, and the unit of epoxy equivalent is g / eq.

The symbol of each component used in the Example is as follows.
XF42-C5277: Polysiloxane polyol (manufactured by Momentive Performance Materials Japan GK, hydroxyl group equivalent 480, average molecular weight 960)
XF42-B0970: Polysiloxane polyol (same as above, hydroxyl group equivalent 960, average molecular weight 1920)
F-510: Aliphatic polyester polyol (Kuraray Co., Ltd., aliphatic polyester polyol (hydroxyl equivalent: 166, average molecular weight: 500)
P-1010: Aliphatic polyester polyol (same as above, hydroxyl group equivalent 500, average molecular weight 1000)
F-3010: Aliphatic polyester polyol (same as above, hydroxyl group equivalent 1000, average molecular weight 3000)
HH: hexahydrophthalic anhydride (acid anhydride group equivalent 154)
CHH: hydrogenated trimellitic anhydride (acid anhydride group equivalent 198)
TGIC: Triglycidyl isocyanurate (epoxy equivalent 100)
Modified TGIC: Propionic anhydride modified triglycidyl isocyanurate (epoxy equivalent 182)
ST-3000: Diglycidyl ether of 2,2-bis (4-hydroxycyclohexyl) propane (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., epoxy equivalent 231)

（式中、ｎは０〜５０の整数を表す。） Synthesis example 1
(Production of modified epoxy resin EA1)
A raw material comprising 187 parts of XF42-C5277 as component (A1) and 62 parts of HH as component (A2) was charged into a 500 ml separable flask equipped with a stirring motor, a reflux condenser, and a nitrogen line. Stirring and temperature increase were started, and after reaching 150 ° C., stirring was continued for 4 hours to synthesize a carboxylic acid compound (A3) having the following formula (4) as a main component. Next, 213 parts of triglycidyl isocyanurate was added as the component (A4), 1.5 parts of triphenylphosphine was added as a reaction catalyst, and the reaction was performed at a reaction temperature of 170 ° C. for 5 hours. As a result of measuring the acid value, it was 0.23 mg KOH / g, and it was confirmed that the carboxyl group reacted with the epoxy group and disappeared, and the modified epoxy resin as the component (A) was obtained. The reaction resin solution was filtered using a 150 mesh wire netting to obtain 436 parts of a modified epoxy resin (A). The name of this modified epoxy resin is (EA1). The epoxy equivalent showed 270.

(In the formula, n represents an integer of 0 to 50.)

Synthesis Examples 2 to 11
(Production of modified epoxy resins EA2 to 11)
A modified epoxy resin (A) was obtained under the same reaction conditions as in Synthesis Example 1 except that each raw material was used in the composition described in Table 1 below as the components (A1) to (A4).

Example 1
(Manufacture of curable epoxy resin composition)
After 63 parts of the modified epoxy resin EA1 obtained as described above and 0.5 parts of HP represented by the above formula (8) as a component (B) are put into a 150 mL stainless steel container and heated to 80 ° C., a vacuum mixer After confirming that the component (B) was uniformly dissolved, add 37 parts of MHH as the component (C) and 0.5 part of PX-4MP as the component (D), and then add the vacuum mixer again. Was mixed to obtain a curable epoxy resin composition. The basis for the amount of MHH added is based on a blending ratio at which the ratio of the epoxy equivalent of the modified epoxy resin EA1 to the acid anhydride group equivalent of MHH is 1: 1.
(Preparation of flat molded product)
This curable epoxy resin composition is poured into a mold having a length of 380 mm and a width of 180 mm provided with a spacer having a thickness of 1 mm, and cured at 120 ° C. for 3 hours and further at 160 ° C. for 6 hours to form a flat plate-shaped product having a thickness of 1 mm. Was made.

Examples 2-15
A curable epoxy resin composition was prepared under the same mixing conditions as in Example 1 except that each raw material was used in the composition described in Table 2 as the components (A) to (D). A flat molded product having a thickness of 1 mm was produced by the same molding method.

Comparative Examples 1-2
(A) Component, (B ′) component, (C) component, curable under the same mixing conditions as in Example 1 except that each raw material was used in the composition described in Table 2 as the component (D). An epoxy resin composition was prepared, and a 1 mm thick plate-like molded product was produced by the same molding technique as in Example 1.

Comparative Examples 3-5
(A ') Curability under the same mixing conditions as in Example 1 except that each raw material was used in the composition described in Table 2 as component (B), component (C), and component (D). An epoxy resin composition was prepared, and a 1 mm thick plate-like molded product was produced by the same molding technique as in Example 1.

Example 16
(Manufacture of curable epoxy resin composition)
96 parts by mass of the modified epoxy resin EA1 obtained as described above, 0.5 part of HP as the component (B), put in a 150 mL stainless steel container and heated to 80 ° C., and then mixed using a vacuum mixer ( B) After confirming that the component was uniformly dissolved, add a solution of 4 parts of DICY uniformly in 30 parts of ethylene glycol monomethyl ether as the component (C), and add PX- as the component (D). 0.5 parts of 4MP was added and mixed again with a vacuum mixer to obtain a curable epoxy resin composition. The basis for the addition amount of DICY is based on a blending ratio in which the ratio of the epoxy equivalent of the modified epoxy resin EA1 to the active hydrogen equivalent of DICY is 1: 0.6.
(Preparation of flat molded product)
This curable epoxy resin composition was dropped on a fluororesin plate provided with a spacer having a thickness of 200 μm and stretched using a glass roll, and left still for 2 hours under the conditions of 20 mmHg and 80 ° C. using a vacuum oven. Eight film-like compositions were produced by carrying out the preliminary reaction of the curable epoxy resin composition while volatilizing the solvent. Next, after eight sheets of the obtained film are placed on a mold provided with a spacer having a thickness of 1 mm and pre-cured by pressing for 10 minutes at 160 ° C. and 20 MPa using a pressure press machine. Then, it was cured at 140 ° C. for 4 hours to produce a 1 mm thick flat plate-shaped product.

Examples 17-21
A curable epoxy resin composition was prepared under the same mixing conditions as in Example 16 except that each raw material was used in the composition described in Table 3 as the components (A) to (D). A flat molded product having a thickness of 1 mm was produced by the same molding method.

Comparative Examples 6-10
(A) Component, (A ′) component, (B ′) component, (C) component, (D) The same as Example 16 except that each raw material was used in the composition described in Table 3 A curable epoxy resin composition was prepared under mixing conditions, and a 1 mm thick plate-like molded product was produced by the same molding technique as in Example 16.

(Preparation of test piece)
The 1 mm flat plate shaped products obtained in Examples 1 to 21 and Comparative Examples 1 to 12 were cut into a size of 40 mm × 25 mm using a plastic cutter, measurement of light transmittance, heat resistance test, which will be described later, Used for light resistance test.

(Measurement of light transmittance)
The value of light transmittance was measured using an ultraviolet-visible spectrophotometer (V-650 manufactured by JASCO Corporation). An integrating sphere unit for focusing the total luminous flux of the light transmitted through the sample is attached, and the light transmittance of 450 nm and 750 nm when the test piece is not set in the sample holder is used as the light transmittance of air, and the value is 100. % T. Next, the test piece of the flat molded product obtained in each Example and Comparative Example was set in a sample holder, and their light transmittances at 450 nm and 750 nm were measured.

(Heat resistance test)
The test piece of the flat molded product was left still in a hot air oven and exposed for 500 hours under the condition of 150 ° C., and then the light transmittance at 450 nm and 750 nm was measured by the same method as the above condition.

(Light resistance test)
The test piece of the flat plate-shaped molded product was placed in a xenon arc lamp irradiation apparatus (manufactured by Sun Test XLS / XLS + manufactured by Toyo Seiki Seisakusho), 600 hours light irradiation energy at 765 W / m ^2, a temperature of 55 ° C. Conditions After that, the light transmittance at 450 nm and 750 nm was measured by the same method as the above conditions.

  Tables 2 and 3 show the results of measurement of light transmittance, heat resistance test, and light resistance test, respectively.

Details of each component in Tables 2 and 3 are as follows: HP: 3,9-bis [1,1-dimethyl-2- [β (3-t-butyl-4-hydroxy-5-methylphenyl] ) Propionyloxy] ethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane (molecular weight 740)
BHT: 2,6-di-t-butyl-p-cresol (molecular weight 220)
MHH: methylhexahydrophthalic anhydride (acid anhydride equivalent 168)
DICY: Dicyandiamide (active hydrogen equivalent 21)
EGM: ethylene glycol monomethyl ether PX-4MP: manufactured by Nippon Chemical Industry Co., Ltd., phosphorus-based curing accelerator U-Cat12XD: manufactured by San Apro, amine-based curing accelerator

  Table 2 shows that by using both a modified epoxy resin (A) component having a polyol structure in the molecule and a phenolic antioxidant (B) having a spiro ring structure and a molecular weight of 500 to 1500, the antioxidant is prevented. A transparent resin composition in which the agent is uniformly dissolved is obtained, and a transparent cured product free from the precipitation of antioxidant crystals can be formed. According to the present invention, the state in which the antioxidant is uniformly dispersed in the molded product is maintained, the antioxidant ability can be maintained for a long time, and there is no bleedout or crystal precipitation of the antioxidant even after the heat resistance test and the light resistance test, A molded product with little yellowing of the molded product is obtained.

  According to the present invention, it is possible to obtain a curable epoxy resin composition that does not cause yellowing of a molded article even during long-term use under high temperatures and outdoors, and is suitable for structural materials, optical materials, and semiconductor materials for outdoor use. Can be used for

Claims (15)

  In an epoxy resin composition comprising a modified epoxy resin (A), a phenolic antioxidant (B) having a molecular weight of 500 to 1500, a curing agent (C), and a curing accelerator (D), a modified epoxy resin ( A) is a polyol (A1) having an alcoholic hydroxyl group and an acid anhydride (A2). The molar ratio of the hydroxyl group to the acid anhydride group of the acid anhydride (A2) in the polyol (A1) is 1: 0.7. Carboxylic acid compound (A3) obtained by addition reaction at a ratio of ˜2.0 to form an ester bond, an average of two or more epoxy groups in the molecule, and an aromatic ring structure in the molecule The modified epoxy resin (A) obtained by reacting the epoxy resin (A4) not reacting at a molar ratio of the carboxyl group of the carboxylic acid compound (A3) and the epoxy group of the epoxy resin (A4) of 1: 3 to 10 There is Curable epoxy resin composition characterized. The polyol (A1) is at least one selected from a polysiloxane polyol represented by the following general formula (1) and a polyester polyol, and has a hydroxyl group equivalent of 150 to 2000 g / eq. The curable epoxy resin composition described in 1.

(In the formula, R ₁ independently represents a methyl group or a phenyl group, and R ₂ independently represents a divalent hydrocarbon group having 2 to 20 carbon atoms which may have an etheric oxygen atom therein. , N represents an integer of 0-50.)   The curable epoxy resin composition according to claim 1 or 2, wherein the epoxy resin (A4) is an epoxy resin having an isocyanuric ring and an average of two or more epoxy groups in the molecule. The phenolic antioxidant (B) is a compound represented by the following general formula (2) having a spiro ring structure, and (A) component, (B) component, (C) component and (D) component The curable epoxy resin composition according to any one of claims 1 to 3, wherein the component (B) is 0.01 to 5.0 mass% with respect to the total amount.

(In the formula, R ₃ represents a divalent hydrocarbon group having 1 to 40 carbon atoms, and may have 2 to 8 ester-bonded oxygen atoms inside. R ₄ is independently a hydrogen atom or Represents a monovalent hydrocarbon group having 1 to 6 carbon atoms.)   The curable epoxy resin composition according to any one of claims 1 to 4, wherein the curing agent (C) is dicyandiamide or diaminodiphenylsulfone.   The curable epoxy resin composition according to any one of claims 1 to 4, wherein the curing agent (C) is an acid anhydride curing agent.   The curable epoxy resin composition according to any one of claims 1 to 6, wherein the curing accelerator (D) is at least one selected from quaternary ammonium salts and quaternary phosphonium salts.   The curable epoxy resin composition according to any one of claims 1 to 7 is obtained by molding and curing, and the light transmittance at 450 nm of a 1 mm-thick flat plate-shaped product is 80% or more, and the light transmittance at 750 nm. A molded product characterized in that the rate is 85% T or more.   The polyol (A1) having an alcoholic hydroxyl group and the acid anhydride (A2) have a molar ratio of the hydroxyl group to the acid anhydride group of the acid anhydride in a polyol molecule of 1: 0.7 to 2.0. The carboxylic acid compound (A4) obtained by the addition reaction with the epoxy resin (A4) having two or more epoxy groups in the molecule and no aromatic ring structure in the molecule. ) And the epoxy resin (A4) have a molar ratio of 1: 3 to 10 to obtain a modified epoxy resin (A), and then a molecular weight of 500 to 1500. A method for producing a curable epoxy resin composition, comprising mixing a phenolic antioxidant (B) and uniformly dissolving, and further mixing a curing agent (C) and a curing accelerator (D).   The curable epoxy resin composition according to any one of claims 1 to 7, which is any one of a resin composition for optical parts, a resin composition for electronic parts, or a resin composition for composite materials.   The curable epoxy resin composition according to claim 10, which is a resin composition for a fiber-reinforced composite material containing reinforcing fibers.   It is a resin composition for optical semiconductor components, The curable epoxy resin composition in any one of Claims 1-7 characterized by the above-mentioned.   The curable epoxy resin composition according to claim 12, which is a white resin composition for an optical semiconductor device containing a white pigment and an inorganic filler.   The LED device using the curable epoxy resin composition of Claim 12 or 13.   A molded article obtained by molding and curing the curable epoxy resin composition according to claim 10.